This invention relates to stable, aqueous solution formulations which are free of products derived from human blood serum and which maintain high biological activity and high chemical and high physical stability of alfa-interferon for an extended period of time.
U.S. Pat. No. 4,496,537 discloses biologically stable alfa interferon aqueous solution formulations containing alfa interferon, human serum albumin and alanine or glycine, water, and a buffer system to maintain the pH at 6.5-8.0. The human serum albumin ("HSA") acts as a stabilizer for alfa interferon and prevents losses of alfa interferon from solution by coating and/or adsorption of the alfa interferon onto the stainless steel and glass surfaces of compounding vessels, process equipment and storage containers. Solution formulations containing alfa interferon and HSA have maintained the chemical and biological stability of the alfa interferon when such solutions have been stored at 2-8.degree. C. for extended periods, i.e., more than 2 years.
Recently, the worldwide AIDS epidemic has resulted in health registration agencies requiring manufacturers to place warnings on products, such as alfa interferon, which contain products derived from human blood such as HSA.
There is a need to reformulate alfa-type interferon solution products to obtain a solution formulation free of human blood-derived products such as HSA while maintaining high chemical, high physical stability and high biological activity for alfa-type interferon in the aqueous solution formulations for extended storage periods.